Instrument having X-ray fluorescence and spark emission spectroscopy analysis capabilities

Abstract

An analytical instrument is disclosed having both XRF and spark emission spectroscopy capabilities. In a particularly advantageous embodiment, a field portable XRF device is removably coupled to the instrument by means of a docking station. A first surface of the sample is irradiated with an X-ray beam, and the X-ray radiation fluorescently emitted from the sample is detected and analyzed to acquire elemental composition data. The instrument is further provided with a spark source located proximal a second surface of the sample and a detector for sensing the radiation emitted from the spark-excited material. The combined instrument enables the acquisition of complementary elemental composition data by XRF and spark emission spectroscopy without having to transport a sample between separate instruments.

Description

FIELD OF THE INVENTION[0001]The present invention relates generally to analytical instruments for measurement of the elemental composition of materials, and more particularly to instruments for X-ray fluorescence and spark emission spectroscopy analysis.BACKGROUND OF THE INVENTION[0002]X-ray fluorescence (XRF) is a well known technology for analysis of the elemental composition of solid materials. In XRF, a focused X-ray beam is directed onto the surface of a sample. Atoms in the sample responsively emit X-ray photons having characteristic energies. One or more X-ray detectors are used to collect and convert the X-rays emitted by the sample into electronic signals that may be processed to determine the energy and number emitted of X-rays, which in turn provides information regarding the abundance of elements in the sample. XRF analyzers are commercially available in both laboratory (stationary) and portable forms. Field portable XRF analyzers situate the X-ray source, detector and r...

AI Technical Summary

Benefits of technology

[0007]In a particularly favorable implementation, the X-ray source and detector(s) are contained in a portable handheld XRF analyzer, which is releasably coupled to the instrument by means of a docking station. The docking station may include one or more attachment features for reproducibly holding the XRF analyzer in a desired position relative to the sample surface. The XRF can then be easily and quickly removed from the instrument and transported to another location for in situ use, and then re-coupled to the instrument for combined XRF / spark emission spectroscopy analysis.

Problems solved by technology

Because the sensitivity of XRF decreases with decreasing proton number (Z), XRF devices are generally not capable of quantitative analysis of light elements in the sample.

For example, portable XRF instruments operating under air (i.e., without purging or evacuation of the region between the analyzer head and the sample) are typically limited to measurement of titanium and heavier elements (Z≧22).

This practice requires the sample to be transported between the instruments, either manually or via a robotic apparatus, which increases the possibility of sample contamination and extends the analysis cycle time.

Although a device architecture of this type (whereby XRF and optical emission spectroscopy data are acquired for a common sample volume) may provide certain advantages in connection with the LIPF technique, it is not well-suited for use with spark emission spectroscopy.

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